カーソル文

次の例は、アプリケーション・プログラムでのカーソル制御文の一般的な順序を示しています。

   ...
/* define a cursor */ 
   EXEC SQL DECLARE emp_cursor CURSOR FOR 
        SELECT ename, job 
        FROM emp 
        WHERE empno = :emp_number 
        FOR UPDATE OF job; 
 
/* open the cursor and identify the active set */ 
   EXEC SQL OPEN emp_cursor; 
 
/* break if the last row was already fetched */ 
   EXEC SQL WHENEVER NOT FOUND DO break; 
 
/* fetch and process data in a loop */ 
   for (;;) 
   { 
      EXEC SQL FETCH emp_cursor INTO :emp_name, :job_title; 
 
/* optional host-language statements that operate on 
   the FETCHed data */ 
 
      EXEC SQL UPDATE emp 
           SET job = :new_job_title 
           WHERE CURRENT OF emp_cursor; 
   } 
... 
/* disable the cursor */ 
   EXEC SQL CLOSE emp_cursor; 
   EXEC SQL COMMIT WORK RELEASE; 
   ...